%%%-------------------------------------------------------------------
%%% @doc Административный обработчик отзывов.
%%% GET   – список отзывов с пагинацией, фильтрацией и сортировкой.
%%% PATCH – массовое обновление статусов отзывов с единой причиной.
%%% @end
%%%-------------------------------------------------------------------
-module(admin_handler_reviews).
-behaviour(cowboy_handler).
-export([init/2]).
-export([trails/0]).

-include("records.hrl").

%%% cowboy_handler callback
init(Req, _Opts) ->
  case cowboy_req:method(Req) of
    <<"GET">> -> list_reviews(Req);
    <<"PATCH">> -> bulk_update_reviews(Req);
    _ -> handler_utils:send_error(Req, 405, <<"Method not allowed">>)
  end.

%%% Swagger metadata
trails() ->
  [ #{ % GET list
    path => <<"/v1/admin/reviews">>,
    method => <<"GET">>,
    description => <<"List all reviews (admin)">>,
    tags => [<<"Reviews">>],
    parameters => [
      #{name => <<"target_type">>, in => <<"query">>, schema => #{type => string}, description => <<"calendar or event">>},
      #{name => <<"target_id">>, in => <<"query">>, schema => #{type => string}, description => <<"ID of target">>},
      #{name => <<"user_id">>, in => <<"query">>, schema => #{type => string}, description => <<"Filter by user">>},
      #{name => <<"status">>, in => <<"query">>, schema => #{type => string}, description => <<"visible, hidden, deleted, or all">>},
      #{name => <<"sort">>, in => <<"query">>, schema => #{type => string, enum => [<<"created_at">>, <<"updated_at">>, <<"rating">>]}, description => <<"Sort field">>},
      #{name => <<"order">>, in => <<"query">>, schema => #{type => string, enum => [<<"asc">>, <<"desc">>]}, description => <<"Sort direction">>},
      #{name => <<"limit">>, in => <<"query">>, schema => #{type => integer}, description => <<"Page size">>},
      #{name => <<"offset">>, in => <<"query">>, schema => #{type => integer}, description => <<"Offset">>}
    ],
    responses => #{
      200 => #{ description => <<"Array of reviews">>, content => #{<<"application/json">> => #{schema => #{ type => array, items => review_schema() }}} }
    }
  },
    #{ % PATCH bulk update
      path => <<"/v1/admin/reviews">>,
      method => <<"PATCH">>,
      description => <<"Bulk update review statuses with a single reason">>,
      tags => [<<"Reviews">>],
      requestBody => #{
        required => true,
        content => #{<<"application/json">> => #{schema => #{
          type => object,
          required => [<<"operations">>, <<"reason">>],
          properties => #{
            <<"operations">> => #{
              type => array,
              items => #{
                type => object,
                properties => #{
                  <<"id">> => #{type => string},
                  <<"status">> => #{type => string, enum => [<<"visible">>, <<"hidden">>, <<"deleted">>]}
                }
              }
            },
            <<"reason">> => #{type => string, description => <<"Reason applied to all updates">>}
          }
        }}}
      },
      responses => #{
        200 => #{description => <<"Number of updated reviews">>},
        400 => #{description => <<"Invalid request body or missing reason">>}
      }
    }
  ].

review_schema() ->
  #{ type => object,
    properties => #{
      id => #{type => string},
      user_id => #{type => string},
      target_type => #{type => string, enum => [<<"calendar">>, <<"event">>]},
      target_id => #{type => string},
      rating => #{type => integer, minimum => 1, maximum => 5},
      comment => #{type => string},
      status => #{type => string, enum => [<<"visible">>, <<"hidden">>, <<"deleted">>]},
      reason => #{type => string, nullable => true},
      likes => #{type => integer},
      dislikes => #{type => integer},
      created_at => #{type => string, format => <<"date-time">>},
      updated_at => #{type => string, format => <<"date-time">>}
    }
  }.

%%% Internal functions

list_reviews(Req) ->
  case handler_utils:auth_admin(Req) of
    {ok, _AdminId, Req1} ->
      Qs = cowboy_req:parse_qs(Req1),
      Filters0 = #{
        target_type => normalize_target_type(proplists:get_value(<<"target_type">>, Qs)),
        target_id => proplists:get_value(<<"target_id">>, Qs),
        user_id => proplists:get_value(<<"user_id">>, Qs),
        status => normalize_status(proplists:get_value(<<"status">>, Qs))
      },
      Filters = maps:filter(fun(_, V) -> V =/= undefined end, Filters0),
      Pagination = handler_utils:parse_pagination_params(Req1),
      {ok, Total, Reviews} = logic_review:list_admin_reviews(Filters, Pagination),
      Json = [handler_utils:review_to_json(R) || R <- Reviews],
      ExtraHeaders = handler_utils:pagination_headers(Pagination, Total),
      handler_utils:send_json(Req1, 200, Json, ExtraHeaders);
    {error, Code, Msg, Req1} ->
      handler_utils:send_error(Req1, Code, Msg)
  end.

%% @private Преобразует бинарный target_type в атом.
normalize_target_type(<<"event">>) -> event;
normalize_target_type(<<"calendar">>) -> calendar;
normalize_target_type(Other) -> Other.

%% @private Преобразует бинарный status в атом.
normalize_status(<<"visible">>) -> visible;
normalize_status(<<"hidden">>) -> hidden;
normalize_status(<<"deleted">>) -> deleted;
normalize_status(Other) -> Other.

bulk_update_reviews(Req) ->
  case handler_utils:auth_admin(Req) of
    {ok, AdminId, Req1} ->
      try
        {ok, Body, Req2} = cowboy_req:read_body(Req1),
        #{<<"operations">> := Operations, <<"reason">> := Reason} = jsx:decode(Body, [return_maps]),
        true = is_list(Operations),
        case logic_review:bulk_update_status(Operations, Reason) of
          {ok, UpdatedCount} ->
            admin_utils:log_admin_action(AdminId, <<"bulk_update_reviews">>, <<"review">>, UpdatedCount, Req2),
            handler_utils:send_json(Req2, 200, #{updated_count => UpdatedCount});
          {error, ReasonErr} ->
            handler_utils:send_error(Req2, 400, ReasonErr)
        end
      catch
        error:{badmatch, _} ->
          handler_utils:send_error(Req1, 400, <<"Missing 'reason' field">>);
        _:_ -> handler_utils:send_error(Req1, 400, <<"Invalid JSON body">>)
      end;
    {error, Code, Msg, Req1} ->
      handler_utils:send_error(Req1, Code, Msg)
  end.